Method and apparatus for manufacture of rayon



May 20, 1941 A. 5. BROWN METHOD AND APPARATUS FOR MANUFACTURE OF RAYON 5 Sheets-Sheet 1 Filed March 11, 1938 INVENTOR q' redfielg Bran/11 H ATTORNEYS I I I l l I I [E May 20, 1941. A. 5. BROWN METHOD AND APPARATUS FOR MANUFACTURE'OF RAYON Filed March 11, 1938 5 Sheets-Sheet 2 INVENTOR flZ/rzg Jag Brawn Hi6 ATTORNEYS May 20, 1941. 5 BROWN 2,243,000

METHOD AND APPARATUS FOR MANUFACTURE OF RAYON Ffiled March 11, 1938 5v Sheets-Sheet 3 14 i 1: r W, 14

15 17 18 1 4 i I 14 I I I 5 /Z7 0 7 U A Q VENTOR flZ/Mg Sea/y Brawn cw mymmwiw Hg; ATTORNEYS May 20; l 4l. A, 5. BROWN 2,243,000

METHOD AND APPARATUS FOR MANUFACTURE OF RAYON Filed March 11, 1938 5 Sheets-Sheet 4 .HHHHIHHHMML l'mnmWH May 20, 1941. A. S.IBROWN METHOD AND APPARATUS FOR MANUFACTURE OF RAYON Filed March 11, 1958 5 Sheets-Sheet s NVENTOR A l ra) Sit/95701011 BY C M 6 A Hz A-n-o lgir l zv s Patented May 20, 1941 METHOD AND APPARATUS FOR MANUFAC- TURE F RAYON Alfred Seely Brown, Hamilton, N. Y., assignor to Skenandoa Rayon Corporation, Utica, N. Y., a

corporation of Delaware Application March 11, 1938, Serial No. 195,364

6 Claims.

This invention relates to the manufacture of rayon, and, more particularly, to new and improved methods and apparatus for treating and processing rayon yarn, primarily in cake form.

Objects of the invention include the provision of new and improved methods and apparatus for treating and processing rayon yarn while in cake form, and, more particularly, for improving uniformity and quality of the yarn; reducing rigidity of the yarn cake before and during the processing of the yarn; producing a softer yarn cake; and producing a better and more uniform quality of the finished yarn.

Other objects of the invention include the following: to improve the bleaching of the yarn; to improve the uniformity of quality of the yarn in different parts of the cake; to reduce harshness which might otherwise occur in the yarn, especially on the outside of the cake; to reduce differences in denier which might otherwise exist between the yarn in different parts of the cake; and to improve the uniformity of textile properties of the yarn from different parts of the yarn cake.

Other objects of the invention will appear from O the following description, and the claims.

In the accompanying drawings:

Figure 1 is a plan view of a spinning bucket which may be used in carrying out the invention;

Figure 2 is a sectional elevation of the same bucket;

Figure 3 is a detailed view of one of the vertical rib members, or slats, which project inwardly from the inner face of the spinning bucket shown in Figure 1;

Figure 4 is a partial, detailed view of adifferent spinning bucket, and of the internal projections or ribs therein provided;

Figure 5 is a partial view of anotherspinning bucket with internal projections;

Figure 6 is a perspective view, diagrammatic in character, of a yarn cake spun in a bucket such as shown in Figures 1 and 2, and thereafter covered with an elastic fabric jacket or stocking, 4

as hereinafter described;

Figure 7 is a plan view of one form of apparatus which may be used in carrying out the invention, for softening a yarn cake, and reducing the diameter thereof, by application to the r apparatus which may be employed for actuating and applying to the yarn cake the apparatus shown in Figures '7 and 8;

Figures 11 and 12 are, respectively, a plan view and a side elevation of another apparatus which may be used for applying substantially tangential force to the outer surface of a yarn cake;

Figure 13 is a partial side elevation, partly in section, of an apparatus which may be used for washing, bleaching and otherwise processing and treating yarn cakes as hereafter explained;

Figure 14 is a side elevation, partly in section, of a centrifugal extraction or whizzing apparatus which may be used in removing excess liquid from yarn cakes prior to drying, as hereafter explained;

Figure 15 is a partial plan View showing, in diagrammatic manner only, the arrangement of the yarn as spun in a spinning bucket like that shown in Figures 1 and 2; and

Figures 16, 17, 18, 19 and 20, are respectively, enlarged partial illustrative views, diagrammatic only, of one form and size of yarn cake as follows: as originally spun; as covered with fabric and ready for application of a cake softener and reducer; as softened and reduced to an extreme position by application of tangential force; as ready for washing, bleaching or other processing; and as finally dried.

Methods and apparatus have heretofore been proposed, both for deforming a yarn cake, and for reducing the diameter of the cake without substantial deformation. An example of the former is the Topham United States Patent No. 1,736,681, granted November 19,1929, in which the cake is first spun in circular form, then washed, thereafter deformed so that it is no longer annular in shape, and dried after such de formation. Examples of the latter include the Mattinson United States Patent No. 2,068,031, granted January 19, 1937, in which there is disclosed a method and apparatus for reducing the diameter of a yarn cake, Without substantial deformation, by subjecting the cake to radial compression at a plurality of spaced points about its periphery; and Patents No. 2,068,032, to Bryant, granted January 19, 1937, and No. 2,068,033, to Mattinson, granted January 19, 1937, in which there are disclosed methods and apparatus for reducing the diameter of yarn cakes by subjecting the cakes to simultaneous radial and axial compression. v

I have discovered that both the quality and uniformity of the completed yarn may be substantially improved, and other desirable objects attained and advantages secured, under certain conditions, by manufacturing the yarn, including initially spinning and subsequently working,

The process may be carried out according to the following example: a rayon yarn cake is first spun in a centrifugal spinning pot, which, while it may be generally circular in cross-section, is

preferably provided, upon its inner surface, with inwardly projecting ribs or what I sometimes call slats, which may be vertical and may extend from top to bottom of the pot in such manner as to provide a particular desired contour of the inner periphery of the spinning pot, as will be hereafter more particularly illustrated and described. Shapes and proportions of spinning pots, and their ribs, which I have found especially advantageous for this purpose are described and claimed in my copending application filed concurrently herewith, Serial No. 195,363; although, under some conditions, a part of the present invention may include the hereafter-described treatment of a cake spun in an ordinary pot. The cake spun in such a ribbed pot has been found, when removed from the spinning pot, to have indentations in its outer periphery, corresponding substantially to the projections on the inside of the pot, as illustrated in the drawings-for ex ample, Figures 16 and 17. The cake may be then next allowed to age for a suitableperiod, although aging is not always necessary, after which it may be encased in a suitable elastic fabric or other protective cover, in the form'of. a jacket or stocking (for example, as described in United States Patent No. 2,002,481 to Gordon and Michel, granted May 21, 1935). The cake may next be softened and, also, reduced in diameter. I have found that a desirable way to carry out that step is by the application to the outer surface of the cake of what is primarily a tan-' gential force, or, at least, a force of which substantial components act primarily tangentially with respect to the outer surface of the cake. Other components of force may or may not be employed simultaneously, as, for example, radial or axial compression; but I have found that advantages reside in the use of primarily tangential force, or, at least, components thereof, for softening the cake and reducing the diameter thereof. The thus-softened and reduced-diameter yarn cake may then be washed, bleached and otherwise processed or treated, as may be required,-for example, in the manner described and claimed in United States Patent to Gordon, No. 1,973,953, granted September 18, 1934, after which the processed cake may be centrifugally extracted or whizzed, to remove excess liquid, and dried. After drying the yarn from the cake may be rewound into acone or other desired form of package for shipment'or fabrication.

Referring now, in greaterdetail, to the accompanying drawings:

In Figure, 1 there is shown, inplan view, a w

spinning pot' Hi which may be used for initially spinning the yarn cake. It is provided; upon its inner surface, with inwardly extending projections H. In the construction shown, these are substantially vertical, and extend throughout the and nine small ribs, of the form shown.

height of the inside of the pot. Figure 2 is a sectional elevation of the same pot, and shows the projections or ribs l I, which I hereinafter sometimes refer to as slats, extending from top to bottom of the spinning area. They may be slightly tapered from top to bottom so that the finished yarn cake may be readily withdrawn from the pot; One shape and form for the ribs or slats H, which may be either integral with the pot, or inserted and secured therein, is shown in detail in Figure 3.

In Figures 4 and 5 are shown other numbers and arrangements of inward projections or ribs which may be used in the spinning pot. In Figure 4 the pot is indicated as having nine large Such an arrangement may be beneficial, under certain conditions, in spinning a soft yarn cake, especially .amendable to uniform processing. In Figure 5 the spinning pot is indicated as having twelve ribs, all of the same height, instead of nine as shown in Figures 1 and 2. This may be advantageous in larger spinning pots, especially if oper- ,ated at higher speeds.

In Figures 6 and 17 are shown two views, the. latter partial and diagrammatic, of'a spun yarn cake l2, in its raw or untreated form, as taken from the spinning pot,'but covered with an elastic fabric or other stocking or jacketlS, as previously described. This assists in protecting the cake during subsequent treatment, but, for best results, the stocking should not be so tight as to prevent subsequent loosening of the cake. In Figure 6 the indentations in the outer part of the cake are diagrammatically indicated inside the stocking; but, in practice, the stocking should not too tightly restrict or compress the cake.

In Figures '7 and 8 there are shown, respectively, plan and sectional elevational views of an apparatus for softening and reducing the diameter of the spun yarn cake by application to the outer surface thereof of substantially or primarily tangential force, in addition to such components of radial force, or radial and axial force, as may also be present or employed, if desired. The apparatus comprises four radially-movable blocks or sectors 14, each provided with a spacing and stop member Ida, for limiting its inward motion to the desired extent. Within the members 14, Ma isan elastic wall i5, suitably made of rubber. It may be of double thickness, as illustrated, and is attached to the movable members 14 by means of vertical rods or pins l5 and the bolts 11, as shown. The rods, l6 are supported at top and bottom by inwardly projecting strips [8 pivotally secured, at their outer ends, to the blocks M, as by screws in-the manner indicated, and free to assume the positions shown. At the bottom of'the apparatus there are arranged fingers l9 which prevent the yarn cake. from dropping out the bottom of the apparatus, and hold the cake in the desired position during and after its treatmentby tangential force; On the outside of the movable members I4 there may be provided suitable rings or hooks, as at 26, by means of which the blocks I4 may be radially separated (as by attachment to the apparatus shown in Figures 9 and 10) to stretchthe'elastic wall i5 to the required diameter for reception of the yarn cake to be treated therein.

Substantially tangential force may be applied to the yarn cake by suitable operation of the apparatus of Figures 7 and 8, as follows:

The mechanism may be actuated by the apparatus shown inFig'ures 9 and 10 to stretch the cake.

rubber sheet; [5:prior to;itszapplicationltoritheoutside :of i the yarn cake, sand :to the :extent'.neces- ,isaryijf or :reception ::of the :cakeLas spun: andicovered. The direction in which the rubber .wall

I5 is stretched is substantiallyfthersamerasfthe longitudinal axis of the threadsron :the outside of the cake. Thus, when:subsequentiyzallowed to contract, the: stretched .rubberfapplies'iwhatis substantially a longitudinal compression to "the outer threads. The mutual adhesion between successive layers :of ithread tends 'itO convey :this

or .soften :the cake .and, :by :the :same::operation,

to reduce its diameter. The ;existerrce:of components of force directed -substantially along the faces 'of the indentations :in ;the 'outerlperiphery of the cake furthertends to loosenthe cakeistruc- :ture'and reduce its diameter. Thuszthe wake indentations form what maybe termed .foci:for the action of the tangential vforce in softening the cake and reducing the diameter thereof.

Contraction of the stretched rubber, .01 other forces, may, also, produce some radial compres- .sion of the'cake, but .the friction of the :rubber withthe outer surface of the'covered cake gives what I believe to be primarily atangential force, 12

or substantial components thereof, which :contributeto the cake 'softeningand reduction, with the results stated.

The spun yarn cake, preferably suitably covered with fabric :as shown in Figuresafi .and .17, f

is inserted within the elastic 'wall l'5 while the latter is in its stretched and extendedposition, which it has assumed due to retraction of the members I4. The elastic I5 is then allow'edto contract upon the cake, and thereby apply to the'outer surface thereof substantial components of tangentialforce, in addition to whatever radial or other .force :may also be applied in the manner stated.

The resulting softened and reduced-diameter yarncake, preferably still encased in its elastic covering 13, may be then transferred to an apparatus for washing and processing the cake. One suitable form of such'an apparatus is shown in Figure 13. It consists ofia series of'processin-g from the cake in a centrifugal extracting or whizzing apparatus such, for example, as shown in Figure 14. In that apparatus, .22 is a centrifugal extractor or whiz-Zing pot mounted upon a suitable spindle 23, and driven by an electric motor 24, as indicated.

Figures 9 and show an apparatus .for actuating the mechanism of Figures 7 and 8 to .stretch the elastic wall preparatory to inserting the cake. The rings or hooks .20 are applied to studs carried by hinged levers 26. When the latter are moved outwardly, the blocks or This may be done sections M are retracted into the position shown inlFi'gure 9, and the elastic wall i5 is sufficiently stretched or expanded so that the covered'yarn cake may be inserted therein. The levers 25 'are the'n permitted Ito return 'to "their initial position by contraction of the rubber, and the'blocks .14 move radially inward until their motion is st'oppe'd by the spacing members 14a, each of which comesinto c'o'ntact each'with its adj acent rmemb'er TM. Iforc'e, anadditional elastic backingor reinforcing member, for strip, 21, suitably of rubber, may, :if desired, be applied outside the rods 16, by

In order to increase the elastic whichlmeans additional force may be applied to "the" yarn icake.

In Figures 1-1 and '12 there is shown another apparatus for applying tangential forces to the outside-of a yarn cake. 'It consists of a number of vertical arms or 'rods 28, twelve in the ar- 1rangement shown, although more maybe used, .mounted at *theirrlov'rer ends upon the radiallymoving sliding plates 29. These are arranged toimove in'the radial slots or guideways '30 in the fixedgplate 3|. Beneath the'radialslides: 29 there 'depend pins 32 carrying rollers 33. These move in'the slots '34 of 'a :rotonily reciprocating cam- :plate 35. A rotary motion may be imparted to this cam :plate, to the extent permitted by the length of theslots'34, by the handle 36,'or otherwise as desired. Rotation of the cam plate 34 serves to retract outwardly the vertical rods or pins 28, to which the rubber or'other elastic'wall 1-5 is attached by the nuts and bolts H, in the manner indicated. In this way the elastic wall l5 may be powerfully "stretched or distended; and, after a yarn cake is inserted therein, subsequent cohtraction of the wall applies a powerful and substantially tangen ial force to the outer surface of the cake, in "the manner previously explained.

Figure 15 shows, in diagrammatic manner, the use and effect of a spinning pot such as those of Figures 1 to 3. The shape of the cake l2, as "spun therein, is illustrated in conjunction with the immediately-following figures, which illustrate, also diagrammaticall successive stages of and changes in a yarn cake when first spun in a pot having the configuration shown -insFig-ure 15, and thereafter subjected to other steps which may be :includedin the instant proc-- ess, 'as will be hereafter described in greater detail.

In carrying out a preferred embodiment of the process in the foregoing apparatus, the principle and operation is as follows:

The rayon is first spun into a yarn cake, in a spinning pot provided with vertical ribs or inward projections, of which suitable forms are shown in Figures 1 to 5 and 15. The cake thus spun is then allowed to age for a suitable time,

if desired, after which it is, preferably, covered, not too tightly, with an elastic cove-ring or stocking, as shown in Figs. 6 and 17. The cake, so covered, is then softened and reduced in diameter by the application to the outer surface thereof of a substantially or primarily tangential force, or components thereof. This may be accomplished by the use of apparatus such as; shown in Figures 7 to 12 inclusive. The cake is then washed, bleached and otherwise processed, which may be done in apparatus such as that shown in Figure 13, after which excess liqis extracted, as by centrifugal whizzing of the cake, which may be done in an apparatus such "as that of Figure 14, and the cake is then I outer layers.

several steps which may be embodied in thel process:

Spinning-By properly proportioning the number, shape, size and relation of the Vertical ribs or projections on the inner face of the spinning pot, and their circumferential spacing, I have found that it is possible to spin a cake having what I call an excess length of yarn, particularly in its That is, the length of the yarn laid down in the ribbed spinning pot, provided with inward projections as described, may be made so" great that when the cake, during subsequent processing (e. g., aging, washing, bleaching, extracting, or drying), subsequently assumes a substantially circular shape, with the indentations diminished or eliminated, such shape involves a,

smaller length of thread in each turn, and the excess length of yarn initially spun into the outer layers of the cake tends to permit a free and natural shrinkage of the yarn to take place upon the outside as well as the inside of the cake.

shown in Figures 1 to 3 are sometimes more advantageous for the purpose with smaller pots, or

at somewhat lower speeds. In addition, the use of ribs or projections i the pot tends to promote subsequent loosening of the cake, and to provide foci for such loosening action, as by the subsequent application of tangential force.

Particular forms of spinning pot, which I have found to be especially advantageous for the purposes just stated, are illustrated in the accompanying drawings and described above, and form the subject-matter of my concurrently pending application, Serial Number 195,363, previously referred to.

Aging.-It is often desirable to permit the spun cake to age between the spinning and subsequent processing steps. This may improve the results of processing, particularly the bleaching, if sufficient aging is used. A suitable aging time has been found to be between twenty-four and forty hours, although more or less may be used. In

some cases, however, aging may be deferred unaging the cake, and the aging step may be omitted under some conditions. 'An important object of the reduction of the cake is to soften and loosen the cake structure to permit better processing and more general and uniform access of the processing liquids during the subsequent operations, often resultinginzmorerapid washing and-other processing treatment, and alsoto permit more uniform shrinkage of the yarn in different parts of the cake, during subsequent stages of the process.

I am aware that it has previously been proposed to deform yarn cakes in various manners; and

. also to reduce the diameter of a yarn cake by the application of substantially radial force, as wellas by the simultaneous application of radial and axial compression. .I have found, however, that it is often advantageous to soften the cake, and also reduce its diameter, by the application to the outer surface thereof of primarily tangential force, or components thereof; preferably without substantial, or, at least, excessive radial compression; but, in any event, in addition to any radial or other compression which may be employed. According to my observation (although I do not desire to limit myself by any particular theory of operation), the application of such substantially tangential force acts in a direction tending to shorten each individual thread longitudinally, assisting the thread to attain its natural shrinkage. It also appears to avoid an initial tendency to pack the yarn cake and a tendency to formation of hard spots and local regions of high rigidity in the cake structure. Accordingly, I have found that by such application of substantially tangential force, improved uniformity of the cake structure, and, particularly, softness of the cake, is promoted, and subsequent processing is rendered easier and more uniform, and may be performed in a substantially shortened time. In addition, I have found that the degree of softening of the yarn .cake may be controlled, so that the operation or slatted spinning pot, as previously described,

tends to facilitate the operation and produces a bake which is more readily loosened by the application of tangential force, and which lends itself to quicker and more uniform processing.

The softening and reduction in diameter of the cake, by application of substantially tangential force thereto, may be carried out either before or after the washing, bleaching, and other processing or purification of the yarn cake. I have found, however, that if the cake is first loosened by the application of tangential force, prior to "the processing step, both the speed and effectiveness of the processing may be substantially increased, and the uniformity of shrinkage is also improved. I ordinarily prefer, therefore, to apply the cake softening and reduction, by tangential force, to the spun cake before it is processed. However, under some circumstances, the cake reduction step may be employed after bleaching and other processing of the cake, in which event,

nevertheless, the uniformity of denier and shrinkage, and the quality and to be improved.

ProcessinQ.During processing and bleaching,

ffeel of the yarn, tends which may be carried .out in the manner shown treatment is improved'by previously loosening the cake by application of tangential force,

When the processing; is; conducted after reduction of the diameter'o-f the cake,-the diameter of the processing pot'may correspond substantially to the diameter of the reduced cake," which has been found to contribute to uniform" processing and shrinkage of the yarn.

Extraction.It is desirable to remove excess liquid from the cakes before placing-them-in adrying oven, and for this process centrifugal extraction or whizzing has-been found useful. The extraction pot may-have a diameter somewhat larger than that of the processed cake, but'theincrease in size should notice so great as to prevent the cake from centering in th'e potortopermit stretching or tensioning of the yarn. I

have also found that the speed-ofthe -'-whizzing pot should preferably be substantially as low -aswill remove a sufficient amount of excess-liquid,

as too high speeds tend to pack-the cake;

Drying-A suitable method of drying to place'the cakes on trays and pass them through a tunnel drier, in which they are dried by meansinvention, so that, when-my-invention -is-em'-- i ployed, drying may be more rapid than might otherwise be possible without/damageto the yarn, which is an additional advantage of the invention.v

As an example of the size and proportion of the apparatus, I have found that, in'-the-case--- of a. 7-inch diameter cake, sufficient loosening of the cake structure, byapplication of'tangential force, may be produced; in certain cases, by reducing the diameter of the cake from 7 inches to about 6.5 inches.

be carried out in whizzing pots havin'g an internal diameter of from about 6.6 to 7 inches.

I have found that when the process is carried out as described, and the foregoing precautions are observed, there is produced a yarn cake having a relatively loose structure, and having a substantially improved uniformity of denier of the yarn in all parts of the cake, an improved feel, and improved quality and uniformity of other physical and textile .characteristics. The uniformity of bleaching and other processing may be substantially improved, possible tendency to harshness of the yarn, especially on the outside of the cake, is reduced, and there is also a substantial reduction in any differences, which might otherwise exist, between the denier and other textile properties of the yarn from the inside and outside of the cake. In addition, uniformity of shrinkage of the yarn, and uniformity of looseness of the cake, both before and after drying, is promoted.

In Figures 16 to 20, inclusive, there is illustrated, in diagrammatic manner only, the shape: and form of a yarn cake, when spun in the manner illustrated in Figure 15, at various subsequent stages of the process. In Figure 16 therei is shown a plan view of a raw cake, as spun in a pot having a series of ribs all of the same height, and having the shape and configuration shown in Figure 15.. The arrangement of the threads is illustrated in purely diagrammatic Th'ecake'may then be washed, processed and otherwise "bleached "in-- buckets having an internal diameter of about 6.6 inches, and the subsequent extra ctionmay manner. Spinning'may, although it need not, be continueduntil the inner layer'of threads is substantiallycircular in cross-section, as shown.

Figure 17 is a partially broken away perspective View of a cake thus spun, after being en'- cased 'inan elastic covering and ready for treat mentby tangential force.

Figure 18 shows a cake as reduc'ed'in diameter to its extreme position, indicating the loosening effect and longitudinal compression of the individual threads.

Figure l9 show' s a 1 cake after the tangential force hasbeen released, and when-the cake is ready. for insertion in the processing pot for washing; bleaching;- and other treatment, and

Figure 20" indicates" diagrammatically the completed,- dried cake, showing the loosened structure, and indicating the uniformity of contraction-of the yarn on the'inside and outside ofthe cakei Approximate dimensions which I have" observed upon cakes treated-in'the manner described are:

For the cake of Figure 16:

Inches Top external diameter 7 Indentation depth i Indentation" base Cake thickness at indentation Cake thickness between indentation i 1 After the tangential forcehas been released, the cake has considerable springiness and' 'tends to'reassume its original shape, hencethe dimensions are only approximate, for the cake of Figure 19:

Inches Top external diameter-i 6%, Indentation depth Indentation base 1 Cake height 4 Cake thickness, all over I 1 The cake is preferably bleached in a pot just large enough to permit it to be slipped easily into place. The pot preferably supports substantially the entire exterior of the cake during the processing operation. The top internal diameter of the pot, for a cake of the foregoing dimensions, may be about 6.5 inches and its height 3% inches, the height of the pot being somewhat less than that of the cake so that the top and bottom of the cake are sealed against leakage, and the processing liquid is forced through the yarn.

The extraction operation may be performed in a pot large enough to permit the cake to be easily introduced and removed therefrom, suitably about 6.5 inches in diameter with a height of 3.8 inches.

For the cake of Figure 20, the approximate dimensions, the cake being dried, are roughly as follows:

Cake height, 3%

The method and apparatus herein described are the best embodiments of my invention now known to me, but it is to be understood that the invention is not necessarily or specifically limited thereto, in all cases, but, under suitable conditions, may be carried out in other ways without departure from its spirit, and within the proper scope of the following claims.

I claim:

1. An apparatus for use in the manufacture of rayon by applying components of substantially tangential primarily compressive force simultaneously over substantially the entire outer surface of a spun rayon yarn cake, comprising an elastic wall member normally smaller in diameter than the outer surface of a rayon yarn cake to be treated therein, and means for stretching said elastic member to a diameter sufiicient to receive the yarn cake and then releasing the stretched wall member to engage the outer surface of the cake and apply components of substantially tangential force thereto.

2. In an apparatus for use in the manufacture of rayon yarn, means for applying substantial components of primarily tangential compressive force simultaneously over substantially the entire outer peripheral surface of a spun yarn cake comprising, in combination; an elastic member adapted to engage the outer periphery of a spun cake to be treated, said member being, in its contracted condition, of less diameter than the periphery of the cake; supporting means associated with the outside of said elastic member; and means for actuating said supporting means to distend the elastic member to a diameter sufficient to receive a yarn cake to be treated therein and thereafter releasing said distended memher and permitting it to contract and. engage the outer periphery of a yarn cake placed therein and apply thereto substantial components of primarily tangential force, by contraction of said elastic member.

3. In a process of manufacturing rayon by the centrifugal bucket spinning system, including spinning a rayon yarn cake in a collecting bucket and thereafter liquid processing the yarn while still in cake form, the method of softening the 5 ithe cake sufiiciently to permit the cake to be inserted within the distended membrane, inserting the cake in said distended membrane, and then permitting the membrane to contract about the cake.

1o}: 4. The method of softening a spun rayon yarn cake to prepare the same for liquid processing treatment of the softened cake, which comprises applying a distended, annular, elastic membrane to the outer peripheral surface of the yarn cake 15;;5and then allowing the membrane to contract about such surface to soften the cake and reduce the diameter thereof.

5. In an apparatus for use in the treatment of spun rayon yarn cakes, means for softening gqggtnd reducing the diameter of such a spun cake, preparatory to liquid processing treatment thereof, which comprises an expansible, annular, elastic membrane having, in its untensioned condition, a diameter substantially less than that of 5;;the outer peripheral surface of the yarn cake to be treated; means for distending said elastic membrane to permit introduction within the expanded membrane of the yarn cake to be treated; and means for subsequently releasing said gggdistended membrane to permit the same to contract upon the outer peripheral surface of the yarn cake and soften the same and reduce the diameter thereof.

6. In a method of treating a spun rayon yarn 353.;jcake to prepare the same for liquid processing,

the steps which comprise inserting the cake within an annular membrane which has a diameter sufficiently great, at the time the cake is inserted,-freely to receive the cake, said membrane be- 40Ting made of a material capable of contracting to a diameter less than that of the outer diameter of the-cake, and causing the membrane to contract about the cake suificiently to exert a substantial compressive force on the, outer pe- 45' 'ripheral surface thereof.

ALFRED SEELY BROWN.

CERTIFICATE OF CORRECTION. Patent No. 2,215,000. ma 20, 191 ALFRED SEELY BROWN.

It is hereby certified that error appears in the printed 'spe cification .of the above numbered patent requiring correction as follows: Page 2, second column, line 19, for "amendable" read amenable; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 211.1210 day of June, A. D. 19b1,

Henry Van Arsdale Acting commissioner of Patents. 

